Tube Pre and SS Power? Or the reverse?

I had the McIntosh MA12000 integrated amplifier which is a hybrid with tubes on the preamplifier and SS on the amp and it was a great component.  McIntosh did this for a reason so I wouldn't question it. 

I’m highly surprised that you’re claiming that 50% of the people suggest a solid state preamp/linestage and a tube power amp.

That generally makes no sense, as the main reason for mixing and matching tubes and ss is to get a tubey sound, which the line stage/preamp has more effect on, and still great bass control by the power amp because of ss power amps higher damping factor and thus better grip on the bass.

You also generally have complexity with tube power amps due to them needing either manual or some kind of automated bias for the driver and output tubes.

The only combination of tube&tube, tube&ss, ss&ss, and ss&tube that doesn't make sense is a ss preamp and a tube power amp. 

I’ve owned many different combinations of preamp/amps and so much depends on the speaker you’re driving.  For my KEF Reference 3’s, the best combo is a tube preamp and a SS amp with ample power.  Currently running LTA MicroZOTL pre, LTA Aero DAC and a Moon 860A V2 amp.  Combo seems to work well for me.  

@mojo771 bimmerlover said it better than I could.  With your room size, SS amplification is likely the way to go.  If you want to add some of the tube magic but also blend into the fold the strengths of SS amplification, the Tube on the front end and SS on the back end can deliver.  I'm not even sure what the reverse gets you and I've never heard of anyone recommending a SS Pre and Tube Amp combo.  I've had all tube, pre & amp in my set up, all SS and a Tube Pre, SS amplification set up.  With the right SS amps, SS always delivered more control, grip and ease. A Tube pre or even the right tube DAC offered a splash of tubbiness without some of the draw backs.  Now, that's with my ears, in my set up, your ears will tell the story, entirely possible to your ears, you'd prefer a SS Pre and Tube Amplification but would think if that's the way you went, you'd want to roll with all tubes at that point.  Good Luck. 

If it must be a mix, tube pre, always. 

I'm a huge fan of the mix, by the way, and find that almost every speaker benefits from the ahem, enhancements (colorations) of the tube pre and a stiff  SS amplifier. 

Of course, quality matters a great deal, but this rule has never let me down.